What you see is what you pay; credits are the same money.
Every price is shown in dollars before you pay. Pay buys exactly what the order costs and spends it on the order at once.
One credit is one US cent. Money that comes back to you (a smaller file than you chose, a declined order) is added as credits, and credits pay for later orders and apps. Your balance is at the top right of every Sucia page.
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